Hydraulic drive device for dump truck

摘要

[PROBLEMS] A hydraulic drive device for preventing an excessive increase in engine speed in body operation. [MEANS FOR SOLVING PROBLEMS] The hydraulic drive device for a dump truck has an generator (8) for outputting the amount of electricity generated according to the rotation speed of an engine (7); a pump-motor (11) driven according to the amount of electricity generated by the generator (8); hydraulic pumps (12a, 12b) driven by the pump-motor (11); a body-raising cylinder (6) for pivoting a body (5), which forms a loading platform, in the up/down direction; an operation amount detection device (14) for detecting the amount of operation of the body-raising cylinder (6); and a control device (19) including a pump-motor power calculation means (19a) for controlling the rotation speed of the engine and obtaining electric power of the pump-motor (11), the electric power corresponding to the operation amount detected by the operation amount detection means (14), and the control device (19) also including a determination means (19b) for determining whether the amount of power generated by the generator (8) is greater than the obtained electric power of the pump-motor (11).